Initial open-source release

packages/context/src/ingest/diff-set.service.ts

@@ -0,0 +1,54 @@
+import type { IngestProvenancePort } from './ports.js';
+import type { DiffSet } from './types.js';
+
+export function computeDiffSetFromHashes(
+  currentHashes: Map<string, string>,
+  priorHashesRaw: Map<string, string>,
+  isPathInScope?: (rawPath: string) => boolean,
+): DiffSet {
+  const priorHashes = isPathInScope
+    ? new Map([...priorHashesRaw].filter(([path]) => isPathInScope(path)))
+    : priorHashesRaw;
+
+  const added: string[] = [];
+  const modified: string[] = [];
+  const unchanged: string[] = [];
+  const deleted: string[] = [];
+
+  for (const [path, hash] of currentHashes) {
+    const prior = priorHashes.get(path);
+    if (prior === undefined) {
+      added.push(path);
+    } else if (prior === hash) {
+      unchanged.push(path);
+    } else {
+      modified.push(path);
+    }
+  }
+
+  for (const path of priorHashes.keys()) {
+    if (!currentHashes.has(path)) {
+      deleted.push(path);
+    }
+  }
+
+  added.sort();
+  modified.sort();
+  unchanged.sort();
+  deleted.sort();
+  return { added, modified, unchanged, deleted };
+}
+
+export class DiffSetService {
+  constructor(private readonly provenance: IngestProvenancePort) {}
+
+  async compute(
+    connectionId: string,
+    sourceKey: string,
+    currentHashes: Map<string, string>,
+    isPathInScope?: (rawPath: string) => boolean,
+  ): Promise<DiffSet> {
+    const priorHashes = await this.provenance.findLatestHashesForCompletedSyncs(connectionId, sourceKey);
+    return computeDiffSetFromHashes(currentHashes, priorHashes, isPathInScope);
+  }
+}